KR101322044B1 - Light Emitting Device and Method for manufacturing thereof - Google Patents

Abstract

The present invention provides a substrate comprising: a first protective layer formed on the substrate and the thin film transistor portion formed on the substrate and the thin film transistor portion having a contact hole exposing a portion of the drain electrode of the thin film transistor portion and the drain electrode of the thin film transistor portion; A second protective layer having a bank disposed on the first electrode and the first electrode and exposing a part of the first electrode, and having a depression formed at one side of the bank, and a light emitting layer formed on the first electrode and a second emitting layer Provided is an electroluminescent device including a light emitting unit including an electrode, and a method of manufacturing the same.

EL, second passivation layer, bank, depression

Description

Light emitting device and method for manufacturing the same

1 is a cross-sectional view showing a conventional active matrix type electroluminescent device.

FIG. 2 is a cross-sectional view showing a cleaning process performed using a cleaning device in a bank region of an active matrix type electroluminescent device shown in FIG.

3A to 3I are process cross-sectional views sequentially showing a manufacturing process diagram of an active matrix type electroluminescent device according to a first embodiment of the present invention.

FIG. 4 is a cross-sectional view showing a cleaning process performed using a cleaning device in a bank region of an active matrix type electroluminescent device shown in FIG. 3H.

FIG. 5 is a cross-sectional view illustrating a process of forming a pattern by mounting a pattern mask corresponding to the bank of the active matrix type electroluminescent device shown in FIG. 3H.

6 is a cross-sectional view of an active matrix type electroluminescent device according to a second embodiment of the present invention.

Description of the Related Art [0002]

201: Chamber 203: Water jet spray

300, 600: active matrix electroluminescent device

302: substrate 304: buffer layer

306: First Polycrystalline Silicon Layer 306a ₁ : Active Layer

306b ₁ : drain region 306c ₁ : source region

307: second polycrystalline silicon layer 307a: capacitor

308: gate insulating film 310: gate electrode

312: first interlayer insulating film 314: power line

316: Second interlayer insulating film 318b ₁ : Drain electrode

318c ₁ Source electrode 320 First protective layer

322: first electrode 324, 624: second protective layer

326: organic light emitting layer 328: second electrode

405: cleaning liquid 407: contaminants

505: pattern mask

A ₁ , A ₂ , A ₃ , A ₄ : 1st, 2, 3, 4 contact hole B ₁ : Bank

C ₁ , C ₂ , C ₃ : depression h ₁ , h ₂ , h ₃ : height difference

S ₂ , S ₃ : slope

The present invention relates to an electroluminescent device and a method of manufacturing the same.

The electroluminescent device is a self-luminous device that emits light by itself, and has a fast response speed and a large luminous efficiency, brightness, and viewing angle. Organic Emitting Light Device, which uses organic materials as the light emitting layer, is capable of emitting various colors, thinning and pattern formation, low DC driving voltage and high luminous efficiency. It is one of the technical field which is being studied very actively.

In particular, the organic electroluminescent device includes an organic light emitting layer between the anode and the cathode so that holes supplied from the anode and electrons received from the cathode combine in the organic light emitting layer to form an exciton, a hole-electron pair, and then the exciton is bottomed. The light emitted by the energy generated when returning to the state.

The organic EL device is classified into a passive matrix organic EL device and an active matrix organic EL device according to a driving method. Here, the active matrix organic electroluminescent device will be described with reference to FIGS. 1 and 2.

1 is a cross-sectional view showing a conventional active matrix type electroluminescent device, and FIG. 2 is a cross-sectional view showing a cleaning process performed using a cleaning device in a bank region of the active matrix type electroluminescent device shown in FIG.

1 and 2, in the conventional active matrix type EL device 100, a buffer layer 104 is formed on a substrate 102.

The first and second polycrystalline silicon layers 106 and 107a or the first and second amorphous silicon layers (not shown) were island patterned on top of the buffer layer 104. In this case, the first polycrystalline silicon layer 106 is divided into the active layer 106a ₁ of the thin film transistor, the drain region 106b ₁ and the source region 106c ₁ doped with impurities, and the second polycrystalline silicon layer 107a. Becomes the capacitor Cst.

The gate insulating layer 108 is formed on the active layer 106a ₁ of the thin film transistor, and the gate electrode 110 is formed on the gate insulating layer 108.

The first interlayer insulating layer 112 is formed on the gate electrode 110. In this case, the first interlayer insulating layer 112 is formed to cover the gate electrode 110, the source and drain regions 106c ₁ and 106b ₁ , and the capacitor 107a.

Power line 114 is formed in a portion on first interlayer insulating film 112. In this case, the power line 114 has a wiring form and extends in one direction, and the second interlayer insulating layer 116 is formed on the power line 114.

In this case, the first interlayer insulating layer 112 and the second interlayer insulating layer 116 have first and second contact holes A ₁ and A ₂ exposing portions of the drain region 106b ₁ and the source region 106c ₁ , respectively. ) And a third contact hole A ₃ exposing a part of the power supply line 114.

The drain electrode 118b ₁ and the source electrode 118c _{1 are} formed on the second interlayer insulating film 116. In this case, the drain electrode 118b ₁ is electrically connected to the drain region 106b ₁ through the first contact hole A ₁ , and the source electrode 118c _{1 is} connected to the second and third contact holes A ₂ ,. A ₃ ) is electrically connected to the source region 106bc ₁ and the power line 114, respectively.

The first passivation layer 120 is formed on the drain electrode 118b ₁ and the source electrode 118c ₁ . In this case, the first passivation layer 120 has a fourth contact hole A ₄ exposing a part of the drain electrode 118b ₁ .

The first electrode 122 is made of a transparent conductive compound material and formed on the first protective layer 120. In this case, the first electrode 122 is an anode or a cathode.

The second protective layer 124 is formed on the first electrode 122. In this case, the second passivation layer 124 has a bank B ₁ exposing a part of the first electrode 122.

The organic emission layer 126 is formed on the bank B ₁ of the second passivation layer 124.

The second electrode 128 is made of an opaque conductive material such as metal and formed on the organic light emitting layer 126. In this case, the second electrode 128 is a cathode or an anode, and formed on the entire surface of the substrate 102.

In this case, as shown in FIG. 2A, the conventional active matrix organic electroluminescent device 100 cleans contaminants existing in the bank B ₁ region before depositing the organic light emitting layer 126. Was carried out.

This cleaning step is to put into the bank (B ₁₎ an active matrix type organic light emitting element 100 having an area for one of the chamber 201, the water jet spray (Water Jet Spray, 203), the bank (B ₁ The cleaning liquid 205 was injected into the () area.

However, as shown in FIG. 2B, the conventional active matrix organic electroluminescent device 100 includes one surface of the second protective layer 124 and the first electrode 122 formed to have the bank B ₁ region. The inclined surface S ₁ formed by one surface of the surface was hurried, and contaminants 207 existed in the bank B ₁ region even after the cleaning process was performed.

Therefore, in the conventional active matrix organic electroluminescent device 100, the organic light emitting layer 126 is deposited on the first electrode 122 in the bank B ₁ region in which the contaminant 207 is present. 122) and the contact force between the organic light emitting layer 126 fell. Accordingly, the conventional active matrix organic EL device 100 has a problem in that power consumption increases due to an increase in wiring resistance.

In addition, the conventional active matrix organic electroluminescent device 100 has a problem that the contaminant 207 can penetrate into the organic light emitting layer 126, thereby reducing the lifespan.

In order to solve the above problems, an object of the present invention is to provide a power consumption can be reduced by lowering the wiring resistance.

It is another object of the present invention to provide a thing which can improve the lifespan by preventing contaminants from penetrating into the organic light emitting layer.

In order to achieve the above object, the present invention includes a substrate, a thin film transistor portion formed on the substrate, and a drain disposed on the thin film transistor portion and having a contact hole exposing a part of the drain electrode of the thin film transistor portion. A second protective layer formed on the first electrode and a first electrode formed to be electrically connected to the electrode, the bank exposing a part of the first electrode, and having a recessed portion at one side of the bank and a light emitting layer formed on the first electrode And a light emitting part including a second electrode on the light emitting layer.

According to another feature of the invention, it is characterized in that at least one depression is formed in the central portion of one side of the bank.

According to another feature of the invention, one side of the bank is characterized in that the height difference with the first electrode is sharply reduced from the top end to the bottom end of the bank.

According to another feature of the invention, the height difference between the depression located close to the top of the bank and the first electrode is characterized in that the 1.3㎛ to 1.7㎛.

According to another feature of the invention, the height difference between the depression and the first electrode located close to the bottom end of the bank is characterized in that 0.3㎛ to 0.7㎛.

According to another feature of the invention, the first electrode is an anode and the second electrode is a cathode.

According to another feature of the invention, the light emitting portion comprises an organic light emitting layer.

According to still another feature of the present invention, there is provided a method of forming a thin film transistor unit on a substrate and a first protection layer formed on the thin film transistor unit to form a first protective layer to have a contact hole exposing a part of a drain electrode of the thin film transistor unit. A first electrode forming step of forming a first electrode so as to be electrically connected to a layer forming step and a drain electrode of the thin film transistor unit, and a bank positioned on the first electrode to expose a portion of the first electrode, and having one side of the bank And a second protective layer forming step of forming a second protective layer so that the recess is patterned by mounting a pattern mask to correspond to the pattern mask.

According to another feature of the invention, the second protective layer forming step is characterized in that the step of forming one or more depressions in the central portion of one side of the bank.

According to another feature of the invention, the second protective layer forming step is characterized in that the step of forming the one side of the bank such that the height difference with the first electrode is sharply reduced from the top end to the bottom end of the bank. .

According to another feature of the invention, the second protective layer forming step is characterized in that the step of forming the height of the recessed portion located close to the top of the bank is 1.3㎛ to 1.7㎛.

According to another feature of the invention, the second protective layer forming step is characterized in that the step of forming so that the height of the recess located close to the bottom end of the bank is 0.3㎛ to 0.7㎛.

According to another feature of the present invention, after the second protective layer forming step includes a light emitting portion forming step of forming a light emitting layer on the first electrode and a second electrode on the light emitting layer.

According to another feature of the invention, the first electrode is an anode and the second electrode is characterized in that the cathode.

According to another feature of the invention, the light emitting portion comprises an organic light emitting layer.

Hereinafter, with reference to the accompanying drawings will be described embodiments of the present invention in more detail.

≪ Embodiment 1 >

3A to 3I are process cross-sectional views sequentially illustrating a manufacturing process diagram of an active matrix type EL device according to a first embodiment of the present invention, and FIG. 4 is a bank region of the active matrix type EL device shown in FIG. 3H. It is sectional drawing for demonstrating performing a washing | cleaning process using a washing | cleaning apparatus.

FIG. 5 is a cross-sectional view illustrating a process of forming a pattern by mounting a pattern mask corresponding to the bank of the active matrix type electroluminescent device shown in FIG. 3H.

Referring to FIG. 3A, an active matrix type electroluminescent device 300 according to a first embodiment of the present invention first forms a buffer layer 304 on a substrate 302, and forms a buffer layer 304 on the buffer layer 304. First and second polycrystalline silicon layers 306 and 307 or first and second amorphous silicon layers (not shown) are formed.

In this case, the first and second polycrystalline silicon layers 306 and 307 or the first and second amorphous silicon layers (not shown) are patterned with a first mask (not shown) to form a semiconductor layer having an island shape.

3B, an insulating film such as a silicon oxide film is deposited on the first and second polycrystalline silicon layers 306 and 307, and a conductive material such as a metal is deposited on the insulating film. The gate insulating layer 308 and the gate electrode 310 are formed by patterning the conductive layer.

Thereafter, impurities are implanted into the first and second polycrystalline silicon layers 306 and 307.

In this case, the active layer 306a ₁ of the thin film transistor not doped with impurities, the drain region 306b ₁ , the source region 306c ₁ doped with impurities, and the capacitors Cst and 307a are formed. Here, the drain region 306b ₁ and the source region 306c ₁ are located at both sides of the active layer 306a ₁ .

3C, a first interlayer insulating film 312 is formed on the gate electrode 310, a conductive material such as a metal is deposited on the first interlayer insulating film 312, and a third mask (not shown). Pattern). In this case, the first interlayer insulating layer 312 is formed to cover the gate electrode 310, the source and drain regions 306c ₁ and 306b ₁ , and the capacitor 107a.

In addition, a power line 314 is formed on a portion of the first interlayer insulating layer 312 corresponding to the capacitors Cst and 307a. The power line 314 extends in one direction in the form of a wire, and is electrically connected to the capacitor 307a.

Thereafter, referring to FIG. 3D, a second interlayer insulating layer 316 is formed on the power line 314, and patterned with a fourth mask (not shown) to form first to third contact holes A ₁ , A ₂ ,. A ₃ ) is formed. In this case, the first contact hole A ₁ exposes a portion of the drain region 306b ₁ , the second contact hole A ₂ exposes a portion of the source region 306c ₁ , and the third contact hole A ₃ ) exposes a portion of power line 314.

Subsequently, referring to FIG. 3E, a conductive material such as a metal is deposited on the second interlayer insulating layer 316 and patterned with a fifth mask (not shown) to form a drain electrode 318b ₁ and a source electrode 318c ₁ . do. At this time, the drain electrode 318b ₁ is electrically connected to the drain region 306b ₁ exposed by the first contact hole A ₁ , and the source electrode 318c _{1 is} connected to the second and third contact holes A _2. , A ₃ is electrically connected to the source region 306c ₁ and the power supply line 314, respectively.

3F, a first protective layer 320 is formed on the drain electrode 318b ₁ and the source electrode 318c ₁ , and is patterned with a sixth mask (not shown) to form the drain electrode 318b ₁ . A _fourth contact hole A ₄ is formed to expose a portion of the fourth contact hole A ₄ .

Through such a sequential manufacturing process, a thin film transistor portion of an active matrix type electroluminescent device according to the present invention is manufactured.

Next, a manufacturing process of sequentially forming light emitting parts on the thin film transistor unit will be described.

Referring to FIG. 3G, an electrode material is deposited on the first passivation layer 320 and patterned with a seventh mask (not shown) to electrically connect with the drain electrode 318b ₁ exposed by the fourth contact hole A ₄ . The first electrode 322 is formed to be connected to each other. In this case, the first electrode 322 may be an anode made of a transparent conductive compound material or a cathode made of an opaque conductive material such as metal.

Subsequently, referring to FIG. 3H, a bank B that forms a second passivation layer 324 on the first electrode 322 and is patterned with an eighth mask (not shown) to expose a portion of the first electrode 322. ₁ ) form.

In this case, as shown in FIG. 5A, the pattern mask 505 is mounted to correspond to one side of the bank B ₁ to be patterned to have a depression C ₁ having a predetermined shape. Such a depression C ₁ is formed by a photolithography method or an etching method.

Here, the recess C ₁ is formed at the center of one side of the bank B ₁ . More specifically speaking, one of the banks (B ₁₎ is formed in a shape in which the smaller the height difference between the banks (B ₁₎ toward the first electrode 322 from the top to the bottom of a sudden.

At this time, the height difference h ₁ between the depression C ₁ and the first electrode 322 is 1.3 μm to 1.7 μm. If the depression C ₁ is 1.3 μm or more, the strength of the bank B ₁ may be increased. If the depression C ₁ is 1.7 μm or less, contaminants present in the bank B ₁ region during the cleaning process may be removed. It can be discharged to outside smoothly.

Subsequently, as shown in FIG. 4A, an active matrix type electroluminescent device 300 having a bank B ₁ region is introduced into one chamber 201 to provide a water jet spray. 203 sprays the cleaning liquid 405 into the bank B ₁ region.

As such, the bank B ₁ having the recess C ₁ on one side smoothes the inclined surface S ₂ formed by one surface of the second protective layer 324 and one surface of the first electrode 322. As shown in FIG. 4B, the pollutant 407 present in the bank B ₁ region can be smoothly discharged to the outside.

Finally, referring to FIG. 3I, an organic emission layer 326 is formed on the bank B ₁ of the second protective layer 324, and a second electrode 328 is formed on the organic emission layer 326.

Here, the second electrode 328 may be a cathode made of an opaque conductive material such as a metal or an anode made of a transparent conductive compound material. In this case, the second electrode 328 is formed on the entire surface of the substrate 302 as a common electrode.

As described above, the active matrix electroluminescent device 300 according to the present invention includes a bank B ₁ having a recess C ₁ , and thus, contaminants present in the bank B ₁ region during the cleaning process ( 407 can be smoothly discharged to the outside.

Accordingly, in the active matrix type EL device 300 according to the present invention, the organic light emitting layer 326 is deposited on the first electrode 322 in the bank B ₁ region without the contaminant 407.

Accordingly, the active matrix electroluminescent device 300 according to the present invention can lower the wiring resistance than the conventional active matrix electroluminescent device 100, thereby reducing power consumption.

In addition, the active matrix type electroluminescent device 300 according to the present invention does not penetrate the contaminant 407 into the organic light emitting layer 326, thereby improving life.

On the other hand, by improving the bank structure of the active matrix type electroluminescent device according to the present invention, the wiring resistance and power consumption can be further lowered, and the life of the organic light emitting layer can be further improved. Such an active matrix type EL device according to another exemplary embodiment of the present invention will be described with reference to FIG. 6.

≪ Embodiment 2 >

6 is a cross-sectional view of an active matrix type electroluminescent device according to a second embodiment of the present invention.

Referring to FIG. 6, the active matrix type electroluminescent device 600 according to the second embodiment of the present invention is provided in the same manner as the active matrix type electroluminescent device 300 according to the first embodiment.

The active matrix type electroluminescent device 600 according to the second embodiment of the present invention is the substrate 302, the buffer layer 304, the same as the active matrix type electroluminescent device 300 according to the first embodiment. The first and second polycrystalline silicon layers 306 and 307a, the active layer 306a ₁ , the drain region 306b ₁ , the source region 306c ₁ , the gate insulating film 308, the gate electrode 310, and the like are included.

In addition, the active matrix EL device 600 according to the second embodiment of the present invention has the same structure as that of the active matrix EL device 300 according to the first embodiment. 314, the second interlayer insulating layer 316, the first and second contact holes A ₁ and A ₂ , the third and fourth contact holes A ₃ , A ₄ ), the drain electrode 318b ₁ , the source electrode 318c ₁ , the first protective layer 320, the first electrode 322, the second protective layer 324, the organic emission layer 326, and the second electrode. (328) is included.

However, the active matrix electroluminescent device 600 according to the second embodiment of the present invention has a recess C ₂ ,. One or more C ₃ ) is formed at the center of one side of the bank B ₁ .

At this time, the height difference h ₂ between the recess C ₂ and the first electrode 322 positioned close to the uppermost end of the bank B ₁ forms 1.3 μm to 1.7 μm. If the depression C ₂ is 1.3 μm or more, the strength of the bank B ₁ may be increased. If the depression C ₂ is 1.7 μm or less, contaminants present in the bank B ₁ region during the cleaning process may be removed. It can be discharged to outside smoothly.

In addition, the height difference h ₃ between the depression C ₃ and the first electrode 322 positioned close to the bottom end of the bank B ₁ may be 0.3 μm to 0.7 μm. If the depression C ₃ is 0.3 μm or more, the strength of the bank B ₁ may be increased. If the depression C ₃ is 0.7 μm or less, contaminants present in the bank B ₁ region during the cleaning process may be removed. It can be discharged to outside smoothly.

As such, the depression C on one side₂, C₃With bank B_One) Is the bank according to the first embodiment (B of Fig. 5)._OneInclined surface S formed by one surface of the second protective layer 324 and one surface of the first electrode 322.₃Smooth).

Accordingly, the active matrix type electroluminescent device 600 according to the second embodiment of the present invention contaminants present in the bank B ₁ region than the active matrix type electroluminescent device 300 according to the first embodiment. It can be discharged to the outside smoothly.

It will be understood by those skilled in the art that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. Therefore, it should be understood that the above-described embodiments are to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than the foregoing description, It is intended that all changes and modifications derived from the equivalent concept be included within the scope of the present invention.

According to the electroluminescent device of the present invention made as described above and a method of manufacturing the same, the following effects can be obtained.

First, the power consumption can be reduced by lowering the wiring resistance.

Second, there is another effect that can improve the lifespan by preventing contaminants from penetrating the organic light emitting layer.

Claims (15)

A substrate; A thin film transistor unit formed on the substrate; A first protective layer on the thin film transistor unit, the first protective layer having a contact hole exposing a portion of the drain electrode of the thin film transistor unit; A first electrode formed to be electrically connected to the drain electrode of the thin film transistor unit; A second protective layer positioned on the first electrode, the bank having a portion exposing a portion of the first electrode, and having a depression formed on one side of the bank; A light emitting part including a light emitting layer formed on the first electrode and a second electrode positioned on the light emitting layer; One side of the bank is an electroluminescent device, characterized in that the height difference with the first electrode is rapidly reduced from the top end to the bottom end of the bank. The method of claim 1, Electroluminescent device, characterized in that at least one depression is formed in the central portion of one side of the bank. delete The method of claim 1, The height difference between the depression located close to the top of the bank and the first electrode is 1.3㎛ to 1.7㎛. The method of claim 1, And a height difference between the depression located close to the bottom of the bank and the first electrode is 0.3 μm to 0.7 μm. The method of claim 1, And the first electrode is an anode, and the second electrode is a cathode. The method of claim 1, The light emitting part includes an organic light emitting layer. Forming a thin film transistor unit on the substrate; Forming a first passivation layer on the thin film transistor unit to form a first passivation layer to have a contact hole exposing a portion of the drain electrode of the thin film transistor unit; Forming a first electrode to be electrically connected to the drain electrode of the thin film transistor unit; A second protective layer positioned on the first electrode to have a bank exposing a portion of the first electrode, and a pattern mask corresponding to one side of the bank to form a second protective layer to pattern the recessed part; A forming step; The second protective layer forming step, And forming one side of the bank such that the height difference with the first electrode decreases rapidly from the top end to the bottom end of the bank. 9. The method of claim 8, The second protective layer forming step, Forming at least one depression in a central portion of one side of the bank. delete 9. The method of claim 8, The second protective layer forming step, And forming a height difference between the depression located near the top of the bank and the first electrode so as to be 1.3 μm to 1.7 μm. 9. The method of claim 8, The second protective layer forming step, And forming a height difference between the depression located close to the lowermost end of the bank and the first electrode so as to be 0.3 μm to 0.7 μm. 9. The method of claim 8, After the second protective layer forming step, And a light emitting part forming step of forming a light emitting layer on the first electrode and a second electrode on the light emitting layer. 9. The method of claim 8, The first electrode is an anode, the second electrode is a manufacturing method of the electroluminescent device, characterized in that the cathode. 14. The method of claim 13, The light emitting part of the electroluminescent device manufacturing method comprising an organic light emitting layer.

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